Junk Plant Watts Bar 1 Pre-Operation Testing

Power Reactor	Event Number: 52177
Facility: WATTS BAR Region: 2 State: TN Unit: [ ] [2] [ ] RX Type: [1] W-4-LP,[2] W-4-LP NRC Notified By: MATTHEW MILLER HQ OPS Officer: DONALD NORWOOD	Notification Date: 08/13/2016 Notification Time: 08:51 [ET] Event Date: 08/13/2016 Event Time: 03:36 [EDT] Last Update Date: 08/13/2016
Emergency Class: NON EMERGENCY 10 CFR Section: 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION	Person (Organization): SCOTT SHAEFFER (R2DO)

Unit	SCRAM Code	RX CRIT	Initial PWR	Initial RX Mode	Current PWR	Current RX Mode
2	N	N	0	Hot Standby	0	Hot Standby

Event Text

AUTOMATIC START OF TURBINE DRIVEN AUXILIARY FEED WATER PUMP "On August 13, 2016 at 0330 EDT, Watts Bar Nuclear Plant Unit 2 (WBN2) was being stabilized following a pre-planned reactor trip. Both motor driven auxiliary feed water pumps and the turbine driven auxiliary feed water pump (TDAFW pump) were in operation maintaining steam generator water level 6 - 50 percent in accordance with the Reactor Trip Response Procedure. "At 0333 EDT the TDAFW pump was secured by procedure and steam generator water level lowered to the Low Low Alarm setpoint (17 percent). The trip time delay

Testing the TDAFW pump.

at 0 percent power is three (3) minutes. At 0336 EDT, the TDAFW pump automatically started with steam generator water levels less than the Low Low alarm setpoint (lowest level reached was 15 percent). "Steam generator water level was restored to the normal shutdown control band (38 percent). "Unit 1 remains in Mode 1 at 85 percent. "Unit 2 is stable in Mode 3 with normal shutdown power alignment. The reactor coolant system is being cooled down to 400 degrees F for a planned maintenance period, with decay heat removal via the Main Condenser Steam dumps and the AFW system. "This event is being reported pursuant to 10 CFR 50.72(b)(3)(iv)(A). "TVA has notified the NRC Resident Inspector."